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<table class="header"><tr class="header"><td class="header">&nbsp;Supported ENVISAT Products</td><td class="header"
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<h2>Map Projection parameters</h2>

<p><font size="+1">&nbsp;&nbsp;Fields of ENVISAT <B>ASAR_Map_GADS</B> Records</font></p>
<table border="1" cellpadding="4" cellspacing="0" width="100%">
<tr>
    <td BGCOLOR="#CCCCFF" CLASS="TableHeadingColor"><font size="+1"> Index</font></td>
    <td BGCOLOR="#CCCCFF" CLASS="TableHeadingColor"><font size="+1"> Identifier</font></td>
    <td BGCOLOR="#CCCCFF" CLASS="TableHeadingColor"><font size="+1"> Field Type</font></td>
    <td BGCOLOR="#CCCCFF" CLASS="TableHeadingColor"><font size="+1"> Field Length</font></td>
    <td BGCOLOR="#CCCCFF" CLASS="TableHeadingColor"><font size="+1"> Description</font></td>
    <td BGCOLOR="#CCCCFF" CLASS="TableHeadingColor"><font size="+1"> Units</font></td>
</tr>
<tr>
    <td>0</td>
    <td><code>"map_descriptor"</code></td>
    <td><a href="../../lang_types.html#String">String</a></td>
    <td>1</td>
    <td>Map projection descriptor one of:<br>UNIVERSAL_TRANSVERSE_MERCATOR, UNIVERSAL_POLAR_STEREOGRAPHIC, LAMBERT_CONFORMAL_CONIC, TRANSVERSE_MERCATOR, MERCATOR, POLAR_STEREOGRAPHIC</td>
    <td>ascii</td>
</tr>
<tr>
    <td>1</td>
    <td><code>"samples"</code></td>
    <td><a href="../../lang_types.html#ULong">ULong</a></td>
    <td>1</td>
    <td>Number of samples per line</td>
    <td>-</td>
</tr>
<tr>
    <td>2</td>
    <td><code>"lines"</code></td>
    <td><a href="../../lang_types.html#ULong">ULong</a></td>
    <td>1</td>
    <td>Number of lines</td>
    <td>-</td>
</tr>
<tr>
    <td>3</td>
    <td><code>"sample_spacing"</code></td>
    <td><a href="../../lang_types.html#Float">Float</a></td>
    <td>1</td>
    <td>Nominal inter-sample distance</td>
    <td>m</td>
</tr>
<tr>
    <td>4</td>
    <td><code>"line_spacing"</code></td>
    <td><a href="../../lang_types.html#Float">Float</a></td>
    <td>1</td>
    <td>Nominal inter-line distance</td>
    <td>m</td>
</tr>
<tr>
    <td>5</td>
    <td><code>"orientation"</code></td>
    <td><a href="../../lang_types.html#Float">Float</a></td>
    <td>1</td>
    <td>Output scene centre orientation</td>
    <td>deg</td>
</tr>
<tr>
    <td>6</td>
    <td><code>"spare_1"</code></td>
    <td><a href="../../lang_types.html#Spare">Spare</a></td>
    <td>1</td>
    <td>Spare</td>
    <td>-</td>
</tr>
<tr>
    <td>7</td>
    <td><code>"heading"</code></td>
    <td><a href="../../lang_types.html#Float">Float</a></td>
    <td>1</td>
    <td>Platform heading, degrees</td>
    <td>deg</td>
</tr>
<tr>
    <td>8</td>
    <td><code>"ellipsoid_name"</code></td>
    <td><a href="../../lang_types.html#String">String</a></td>
    <td>1</td>
    <td>Reference ellipsoid name</td>
    <td>ascii</td>
</tr>
<tr>
    <td>9</td>
    <td><code>"semi_major"</code></td>
    <td><a href="../../lang_types.html#Float">Float</a></td>
    <td>1</td>
    <td>Ellipsoid semi-major axis, metres</td>
    <td>m</td>
</tr>
<tr>
    <td>10</td>
    <td><code>"semi_minor"</code></td>
    <td><a href="../../lang_types.html#Float">Float</a></td>
    <td>1</td>
    <td>Ellipsoid semi-minor axis, metres</td>
    <td>m</td>
</tr>
<tr>
    <td>11</td>
    <td><code>"shift_dx"</code></td>
    <td><a href="../../lang_types.html#Float">Float</a></td>
    <td>1</td>
    <td>Datum shift parameter referenced to Greenwich: dx (metres)</td>
    <td>m</td>
</tr>
<tr>
    <td>12</td>
    <td><code>"shift_dy"</code></td>
    <td><a href="../../lang_types.html#Float">Float</a></td>
    <td>1</td>
    <td>Datum shift parameter perpendicular to Greenwich: dy (metres)</td>
    <td>m</td>
</tr>
<tr>
    <td>13</td>
    <td><code>"shift_dz"</code></td>
    <td><a href="../../lang_types.html#Float">Float</a></td>
    <td>1</td>
    <td>Datum shift parameter direction of the rotation axis: dz (metres)</td>
    <td>m</td>
</tr>
<tr>
    <td>14</td>
    <td><code>"avg_height"</code></td>
    <td><a href="../../lang_types.html#Float">Float</a></td>
    <td>1</td>
    <td>average scene height above ellipsoid used for geocoding</td>
    <td>-</td>
</tr>
<tr>
    <td>15</td>
    <td><code>"spare_2"</code></td>
    <td><a href="../../lang_types.html#Spare">Spare</a></td>
    <td>1</td>
    <td>Spare</td>
    <td>-</td>
</tr>
<tr>
    <td>16</td>
    <td><code>"projection_description"</code></td>
    <td><a href="../../lang_types.html#String">String</a></td>
    <td>1</td>
    <td>Map projection alphanumeric description</td>
    <td>ascii</td>
</tr>
<tr>
    <td>17</td>
    <td><code>"utm_descriptor"</code></td>
    <td><a href="../../lang_types.html#String">String</a></td>
    <td>1</td>
    <td>UTM descriptorUNIVERSAL_TRANSVERSE_MERCATOR&Oslash;&Oslash;&Oslash;</td>
    <td>ascii</td>
</tr>
<tr>
    <td>18</td>
    <td><code>"utm_zone"</code></td>
    <td><a href="../../lang_types.html#String">String</a></td>
    <td>1</td>
    <td>UTM zone signature</td>
    <td>ascii</td>
</tr>
<tr>
    <td>19</td>
    <td><code>"utm_origin_easting"</code></td>
    <td><a href="../../lang_types.html#Float">Float</a></td>
    <td>1</td>
    <td>Map origin, false easting</td>
    <td>m</td>
</tr>
<tr>
    <td>20</td>
    <td><code>"utm_origin_northing"</code></td>
    <td><a href="../../lang_types.html#Float">Float</a></td>
    <td>1</td>
    <td>Map origin, false northing</td>
    <td>m</td>
</tr>
<tr>
    <td>21</td>
    <td><code>"utm_center_long"</code></td>
    <td><a href="../../lang_types.html#SLong">SLong</a></td>
    <td>1</td>
    <td>Projection centre longitude, deg</td>
    <td>(1e-6) degrees</td>
</tr>
<tr>
    <td>22</td>
    <td><code>"utm_center_lat"</code></td>
    <td><a href="../../lang_types.html#SLong">SLong</a></td>
    <td>1</td>
    <td>Projection centre latitude, deg</td>
    <td>(1e-6) degrees</td>
</tr>
<tr>
    <td>23</td>
    <td><code>"utm_para1"</code></td>
    <td><a href="../../lang_types.html#Float">Float</a></td>
    <td>1</td>
    <td>1st standard parallel, deg</td>
    <td>deg</td>
</tr>
<tr>
    <td>24</td>
    <td><code>"utm_para2"</code></td>
    <td><a href="../../lang_types.html#Float">Float</a></td>
    <td>1</td>
    <td>2nd standard parallel, deg</td>
    <td>deg</td>
</tr>
<tr>
    <td>25</td>
    <td><code>"utm_scale"</code></td>
    <td><a href="../../lang_types.html#Float">Float</a></td>
    <td>1</td>
    <td>Scale factor</td>
    <td>-</td>
</tr>
<tr>
    <td>26</td>
    <td><code>"ups_descriptor"</code></td>
    <td><a href="../../lang_types.html#String">String</a></td>
    <td>1</td>
    <td>UPS descriptor</td>
    <td>ascii</td>
</tr>
<tr>
    <td>27</td>
    <td><code>"ups_center_long"</code></td>
    <td><a href="../../lang_types.html#SLong">SLong</a></td>
    <td>1</td>
    <td>Projection centre longitude, deg</td>
    <td>(1e-6) degrees</td>
</tr>
<tr>
    <td>28</td>
    <td><code>"ups_center_lat"</code></td>
    <td><a href="../../lang_types.html#SLong">SLong</a></td>
    <td>1</td>
    <td>Projection centre latitude, deg</td>
    <td>(1e-6) degrees</td>
</tr>
<tr>
    <td>29</td>
    <td><code>"ups_scale"</code></td>
    <td><a href="../../lang_types.html#Float">Float</a></td>
    <td>1</td>
    <td>Scale factor</td>
    <td>-</td>
</tr>
<tr>
    <td>30</td>
    <td><code>"nsp_descriptor"</code></td>
    <td><a href="../../lang_types.html#String">String</a></td>
    <td>1</td>
    <td>NSP descriptor</td>
    <td>ascii</td>
</tr>
<tr>
    <td>31</td>
    <td><code>"origin_easting"</code></td>
    <td><a href="../../lang_types.html#Float">Float</a></td>
    <td>1</td>
    <td>Map origin, false easting</td>
    <td>m</td>
</tr>
<tr>
    <td>32</td>
    <td><code>"origin_northing"</code></td>
    <td><a href="../../lang_types.html#Float">Float</a></td>
    <td>1</td>
    <td>Map origin, false northing</td>
    <td>m</td>
</tr>
<tr>
    <td>33</td>
    <td><code>"center_long"</code></td>
    <td><a href="../../lang_types.html#SLong">SLong</a></td>
    <td>1</td>
    <td>Projection centre longitude, deg</td>
    <td>(1e-6) degrees</td>
</tr>
<tr>
    <td>34</td>
    <td><code>"center_lat"</code></td>
    <td><a href="../../lang_types.html#SLong">SLong</a></td>
    <td>1</td>
    <td>Projection centre latitude, deg</td>
    <td>(1e-6) degrees</td>
</tr>
<tr>
    <td>35</td>
    <td><code>"standard_parallel_parameters.para1"</code></td>
    <td><a href="../../lang_types.html#Float">Float</a></td>
    <td>1</td>
    <td>Standard parallel1, deg</td>
    <td>deg</td>
</tr>
<tr>
    <td>36</td>
    <td><code>"standard_parallel_parameters.para2"</code></td>
    <td><a href="../../lang_types.html#Float">Float</a></td>
    <td>1</td>
    <td>Standard parallel2, deg</td>
    <td>deg</td>
</tr>
<tr>
    <td>37</td>
    <td><code>"standard_parallel_parameters.para3"</code></td>
    <td><a href="../../lang_types.html#Float">Float</a></td>
    <td>1</td>
    <td>Standard parallel3, deg</td>
    <td>deg</td>
</tr>
<tr>
    <td>38</td>
    <td><code>"standard_parallel_parameters.para4"</code></td>
    <td><a href="../../lang_types.html#Float">Float</a></td>
    <td>1</td>
    <td>Standard parallel4, deg</td>
    <td>deg</td>
</tr>
<tr>
    <td>39</td>
    <td><code>"central_meridian_parameters.central_m1"</code></td>
    <td><a href="../../lang_types.html#Float">Float</a></td>
    <td>1</td>
    <td>Central meridian1, deg</td>
    <td>deg</td>
</tr>
<tr>
    <td>40</td>
    <td><code>"central_meridian_parameters.central_m2"</code></td>
    <td><a href="../../lang_types.html#Float">Float</a></td>
    <td>1</td>
    <td>Central meridian2, deg</td>
    <td>deg</td>
</tr>
<tr>
    <td>41</td>
    <td><code>"central_meridian_parameters.central_m3"</code></td>
    <td><a href="../../lang_types.html#Float">Float</a></td>
    <td>1</td>
    <td>Central meridian3, deg</td>
    <td>deg</td>
</tr>
<tr>
    <td>42</td>
    <td><code>"projection_parameters.spare_3"</code></td>
    <td><a href="../../lang_types.html#Spare">Spare</a></td>
    <td>1</td>
    <td>Spare</td>
    <td>-</td>
</tr>
<tr>
    <td>43</td>
    <td><code>"projection_parameters.spare_4"</code></td>
    <td><a href="../../lang_types.html#Spare">Spare</a></td>
    <td>1</td>
    <td>Spare</td>
    <td>-</td>
</tr>
<tr>
    <td>44</td>
    <td><code>"projection_parameters.spare_5"</code></td>
    <td><a href="../../lang_types.html#Spare">Spare</a></td>
    <td>1</td>
    <td>Spare</td>
    <td>-</td>
</tr>
<tr>
    <td>45</td>
    <td><code>"projection_parameters.spare_6"</code></td>
    <td><a href="../../lang_types.html#Spare">Spare</a></td>
    <td>1</td>
    <td>Spare</td>
    <td>-</td>
</tr>
<tr>
    <td>46</td>
    <td><code>"position_northings_eastings.tl_northing"</code></td>
    <td><a href="../../lang_types.html#Float">Float</a></td>
    <td>1</td>
    <td>Top left corner northing, meters;</td>
    <td>m</td>
</tr>
<tr>
    <td>47</td>
    <td><code>"position_northings_eastings.tl_easting"</code></td>
    <td><a href="../../lang_types.html#Float">Float</a></td>
    <td>1</td>
    <td>Top left corner easting, meters;</td>
    <td>m</td>
</tr>
<tr>
    <td>48</td>
    <td><code>"position_northings_eastings.tr_northing"</code></td>
    <td><a href="../../lang_types.html#Float">Float</a></td>
    <td>1</td>
    <td>Top right corner northing, meters;</td>
    <td>m</td>
</tr>
<tr>
    <td>49</td>
    <td><code>"position_northings_eastings.tr_easting"</code></td>
    <td><a href="../../lang_types.html#Float">Float</a></td>
    <td>1</td>
    <td>Top right corner easting, meters;</td>
    <td>m</td>
</tr>
<tr>
    <td>50</td>
    <td><code>"position_northings_eastings.br_northing"</code></td>
    <td><a href="../../lang_types.html#Float">Float</a></td>
    <td>1</td>
    <td>Bottom right corner northing, meters;</td>
    <td>m</td>
</tr>
<tr>
    <td>51</td>
    <td><code>"position_northings_eastings.br_easting"</code></td>
    <td><a href="../../lang_types.html#Float">Float</a></td>
    <td>1</td>
    <td>Bottom right corner easting, meters;</td>
    <td>m</td>
</tr>
<tr>
    <td>52</td>
    <td><code>"position_northings_eastings.bl_northing"</code></td>
    <td><a href="../../lang_types.html#Float">Float</a></td>
    <td>1</td>
    <td>Bottom left corner northing, meters;</td>
    <td>m</td>
</tr>
<tr>
    <td>53</td>
    <td><code>"position_northings_eastings.bl_easting"</code></td>
    <td><a href="../../lang_types.html#Float">Float</a></td>
    <td>1</td>
    <td>Bottom left corner easting, meters;</td>
    <td>m</td>
</tr>
<tr>
    <td>54</td>
    <td><code>"position_lat_long.tl_lat"</code></td>
    <td><a href="../../lang_types.html#SLong">SLong</a></td>
    <td>1</td>
    <td>Top left corner latitude</td>
    <td>(1e-6) degrees</td>
</tr>
<tr>
    <td>55</td>
    <td><code>"position_lat_long.tl_long"</code></td>
    <td><a href="../../lang_types.html#SLong">SLong</a></td>
    <td>1</td>
    <td>Top left corner longitude</td>
    <td>(1e-6) degrees</td>
</tr>
<tr>
    <td>56</td>
    <td><code>"position_lat_long.tr_lat"</code></td>
    <td><a href="../../lang_types.html#SLong">SLong</a></td>
    <td>1</td>
    <td>Top right corner latitude</td>
    <td>(1e-6) degrees</td>
</tr>
<tr>
    <td>57</td>
    <td><code>"position_lat_long.tr_long"</code></td>
    <td><a href="../../lang_types.html#SLong">SLong</a></td>
    <td>1</td>
    <td>Top right corner longitude</td>
    <td>(1e-6) degrees</td>
</tr>
<tr>
    <td>58</td>
    <td><code>"position_lat_long.br_lat"</code></td>
    <td><a href="../../lang_types.html#SLong">SLong</a></td>
    <td>1</td>
    <td>Bottom right corner latitude</td>
    <td>(1e-6) degrees</td>
</tr>
<tr>
    <td>59</td>
    <td><code>"position_lat_long.br_long"</code></td>
    <td><a href="../../lang_types.html#SLong">SLong</a></td>
    <td>1</td>
    <td>Bottom right corner longitude</td>
    <td>(1e-6) degrees</td>
</tr>
<tr>
    <td>60</td>
    <td><code>"position_lat_long.bl_lat"</code></td>
    <td><a href="../../lang_types.html#SLong">SLong</a></td>
    <td>1</td>
    <td>Bottom left corner latitude</td>
    <td>(1e-6) degrees</td>
</tr>
<tr>
    <td>61</td>
    <td><code>"position_lat_long.bl_long"</code></td>
    <td><a href="../../lang_types.html#SLong">SLong</a></td>
    <td>1</td>
    <td>Bottom left corner longitude</td>
    <td>(1e-6) degrees</td>
</tr>
<tr>
    <td>62</td>
    <td><code>"spare_7"</code></td>
    <td><a href="../../lang_types.html#Spare">Spare</a></td>
    <td>1</td>
    <td>Spare</td>
    <td>-</td>
</tr>
<tr>
    <td>63</td>
    <td><code>"image_to_map_coefs"</code></td>
    <td><a href="../../lang_types.html#Float">Float</a></td>
    <td>8</td>
    <td>8 coefficients to convert a line(L) and sample (S) position to the map projection frame of reference, say (E,N)E
        = A11 + A12*L + A13 *S + A14 *L*SN = A21 + A22*L + A23 *S + A24 *L*S</td>
    <td>-</td>
</tr>
<tr>
    <td>64</td>
    <td><code>"map_to_image_coefs"</code></td>
    <td><a href="../../lang_types.html#Float">Float</a></td>
    <td>8</td>
    <td>8 coefficients to convert from the map projection (E,N) to line (L) and sample(S) position in the imageL = B11 +
        B12*E + B13 *N + B14 *E*NS = B21 + B22*E + B23 *N + B24 *E*N</td>
    <td>-</td>
</tr>
<tr>
    <td>65</td>
    <td><code>"spare_8"</code></td>
    <td><a href="../../lang_types.html#Spare">Spare</a></td>
    <td>1</td>
    <td>Spare</td>
    <td>-</td>
</tr>
</table>
</body>
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